Mechanical movement



UNITED STATES PATT OFFICE.

JOHN H. WAIT, OF PORTSMOUTH, OHIO.

MECHANICAL MOVEMENT.

Specification of Letters Patent No. 28,318, dated May 15, 1860.

T o all whom it may concern:

' Be it known that I, JOHN H. WAIT, of Portsmouth, Scioto county, Ohio, have invented a new and Improved Mechanical Movement; and I hereby declare the following to be a full and exact description of the nature and operation of the same, reference being had to the accompanying drawings, making a part of this specification.

The leading feature of novelty in my said invention consists of a crank or rock shaft formed with an elongated wrist oblique to its axis of rotation and adapted to impart a variable reciprocating motion to a pitman journaled adjustably thereon, as will be hereinafter more fully described.

The accompanying drawings illustrate several modifications of the invention.

Figure l is a longitudinal sectional elevation, Fig. 2, an end elevation and Fig. 3 a plan.

A is a frame affording journal bearings for crank shafts B B.

C is a crank arm attached to the shaft B.

D is an elongated oblique wrist extending from the outer end of the arm C to the shaft B.

E is a pitman connected to the wrist D by a box c, pivoted so as to admit of its oscillation in respect to the pitman as the crank rotates.

F is a rod connecting the pitman by means of ball and socket joints, with a crosshead Gr sliding upon ways H.

I is a lever having its fulcrum at t', and attached to the crosshead at g, for the pur pose of moving the same in either direction so as to give the pitman a greater or less throw by changing its position upon the wrist D.

In the position shown in Fig. l the center of the box e is coincident with the axis of the shafts B and B and the rotation of the crank C D will therefore produce no longitudinal motion of the pitman E but by changing t-he pitman to the position exhibited in Fig. 3 so as to bring the box e in proximity with the arm C it will have the greatest length of stroke within the capacity of the crank and a stroke of any desired length can be obtained by fixing it in any intermediate position.

The lever I is provided with a spring catch j engaging with a rack J so as to hold the lever firmly in any position whichy it may be set; but offer no resistance to its adjustment by hand.

C and O2 represent arms and D the wrist of an oblique crank of modified form. In this case the center of the wrist is coincident with' the axis of the journals while its respective ends extend therefrom on opposite sides. A continuous motion of this crank may be made to impart a reverse motion to the pit-man by changing the latter from end to end of the wrist D, while by fixing it in the center of the wrist it will remain quiescent.

K and L illustrate the invention applied to rock shafts. K is an oblique shaft projecting on both side of the axis of rotation and operating on the same principle as the duplex crank C' C2 D7 excepting that it has anoscillating instead of a continuous rotary motion. L is an oblique wrist connected at its respective ends to the shaft plroper by arms l and Z forming radii 90 egrees apart instead of 180 degrees as in the previous illustration. In this case the changing of the pitman from end to end of the wrist will change the time of the stroke to one half the extent previously explained.

I claim as new and of my invention herein Constructing a crank with an elongated wrist pin set obliquely to its axis of rotation, so that a pitman connected thereto can be made to give any desired length of stroke or throw within the capacity of the crank without retarding the motion thereof, in the manner substantially as hereinbefore described.

In testimony of which invention, I hereunto set my hand.

J. H. WAIT.

Witnesses J AMES H. GRIDLEY, JOHN W. CLUTE. 

